A rough and fine drawing structure spline broach and its design method

Abstract

The invention discloses a rough and fine drawing structure spline broach and a design method thereof. The disclosed broach includes a spline cutting tooth, and the spline cutting tooth includes a plurality of concentrically arranged knife tooth rings along the cutting direction, two adjacent knife tooth rings form a group of knife tooth rings, and each group of knife tooth rings consists of a The rough broaching tooth ring and a finishing broaching tooth ring are composed of a rough broaching tooth top with concave fillets on both sides; The amount of lift is the same, and the tooth lift of each group of cutter rings is the same, and the tooth lift of the fine-drawn teeth of the same group of cutter rings is smaller than that of the rough-drawn teeth. The disclosed method is the design method of the broach of the present invention. This broach has a certain resistance to edge chipping. When chipping occurs, because the rough-drawing tooth does not participate in the formation of the final tooth profile, it will not affect the processing quality of the gear tooth surface; Small and durable.

Description

technical field [0001] The invention relates to a tool for machining, in particular to a spline broach with a fine and rough drawing structure. Background technique [0002] At present, involute spline or rectangular spline broaches at home and abroad usually adopt a single-tooth involute machining structure. All the teeth are concentric circles. During the cutting process, the latter tooth is higher than the previous one. A layer of metal is removed from one tooth, and the processing of the spline tooth shape is completed layer by layer. Since each tooth is involved in the processing of the spline tooth profile, any tooth on the broach has abnormal phenomena such as chipping and wear. After that, it will cause roughness defects on the gear tooth profile. When the workpiece material is hard or the gear tooth profile roughness is required to be high, the number of broach sharpening at one time is very small, and the processing cost is high. SUMMARY OF THE INVENTION [0003...

AI Technical Summary

Problems solved by technology

[0002] At present, involute spline or rectangular spline broaches at home and abroad usually adopt a single-tooth progressive processing structure, and all the teeth are concentric circles. During the cutting process, the latter tooth is higher than the previous tooth. One tooth pulls off a layer of metal, and completes the processing of the spline tooth shape layer by layer. Since each tooth is involved in the processing of the spline tooth profile, any abnormal phenomenon such as chipping and wear on any tooth on the broach Finally, it will cause roughness defects on the gear tooth profile. When the workpiece material is hard or the gear tooth profile roughness requirements are high, the number of broach sharpening is very small, and the processing cost is high.

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